diff --git a/Gopkg.lock b/Gopkg.lock
index cfad1f2..15720c6 100644
--- a/Gopkg.lock
+++ b/Gopkg.lock
@@ -2,82 +2,113 @@
 
 
 [[projects]]
+  digest = "1:8722889ad027febfced94665914d1e7be8f1b703d31f2ef9461c59e4d40fe974"
   name = "github.com/certifi/gocertifi"
   packages = ["."]
+  pruneopts = ""
   revision = "deb3ae2ef2610fde3330947281941c562861188b"
   version = "2018.01.18"
 
 [[projects]]
+  digest = "1:0deddd908b6b4b768cfc272c16ee61e7088a60f7fe2f06c547bd3d8e1f8b8e77"
   name = "github.com/davecgh/go-spew"
   packages = ["spew"]
+  pruneopts = ""
   revision = "8991bc29aa16c548c550c7ff78260e27b9ab7c73"
   version = "v1.1.1"
 
 [[projects]]
+  digest = "1:023fbbe144662cdcd931f9c47e29e5a0f89d01d340600c270aaaf887fe667edc"
   name = "github.com/mastahyeti/certstore"
   packages = ["."]
-  revision = "6f2394a25c204d281922fe1407d4385a7b979963"
-  version = "0.0.3"
+  pruneopts = ""
+  revision = "c84a6bb0b6baafd35a9316317b4621c9d04c6813"
+  version = "0.0.4"
 
 [[projects]]
+  digest = "1:26ab843f72f1e7b54b7ad984510a956926e623f880a26faca9375d2199d928d2"
   name = "github.com/mastahyeti/cms"
   packages = [
     ".",
     "oid",
     "protocol",
-    "timestamp"
+    "timestamp",
   ]
+  pruneopts = ""
   revision = "a229af0c48a09fb2fd15983d09eb47052521ce03"
   version = "0.0.2"
 
 [[projects]]
   branch = "master"
+  digest = "1:915b4b548d2fc9dbead609376aabf7a95d0cb8764501d2a451495f7d394635b6"
   name = "github.com/mastahyeti/fakeca"
   packages = ["."]
+  pruneopts = ""
   revision = "5f91b32d1226951f9631342eee20f5142387a216"
 
 [[projects]]
   branch = "master"
+  digest = "1:67235b35254a10a1763d608067d34cafaf88457c4054755a8b26a68b6a934ed3"
   name = "github.com/pborman/getopt"
   packages = ["v2"]
+  pruneopts = ""
   revision = "2b5b3bfb099b7da3e2f433966f8ab1d5803e0876"
 
 [[projects]]
+  digest = "1:7365acd48986e205ccb8652cc746f09c8b7876030d53710ea6ef7d0bd0dcd7ca"
   name = "github.com/pkg/errors"
   packages = ["."]
+  pruneopts = ""
   revision = "645ef00459ed84a119197bfb8d8205042c6df63d"
   version = "v0.8.0"
 
 [[projects]]
+  digest = "1:256484dbbcd271f9ecebc6795b2df8cad4c458dd0f5fd82a8c2fa0c29f233411"
   name = "github.com/pmezard/go-difflib"
   packages = ["difflib"]
+  pruneopts = ""
   revision = "792786c7400a136282c1664665ae0a8db921c6c2"
   version = "v1.0.0"
 
 [[projects]]
+  digest = "1:c587772fb8ad29ad4db67575dad25ba17a51f072ff18a22b4f0257a4d9c24f75"
   name = "github.com/stretchr/testify"
   packages = [
     "assert",
-    "require"
+    "require",
   ]
+  pruneopts = ""
   revision = "f35b8ab0b5a2cef36673838d662e249dd9c94686"
   version = "v1.2.2"
 
 [[projects]]
   branch = "master"
+  digest = "1:b2d8b39397ca07929a3de3a3fd2b6ca4c8d48e9cadaa7cf2b083e27fd9e78107"
   name = "golang.org/x/crypto"
   packages = [
     "cast5",
     "openpgp/elgamal",
     "openpgp/errors",
     "openpgp/packet",
-    "openpgp/s2k"
+    "openpgp/s2k",
   ]
+  pruneopts = ""
   revision = "0709b304e793a5edb4a2c0145f281ecdc20838a4"
 
 [solve-meta]
   analyzer-name = "dep"
   analyzer-version = 1
-  inputs-digest = "beee101522fbba0ef4524626104699e2a2252d63076c4aa575c1b602a93adda6"
+  input-imports = [
+    "github.com/certifi/gocertifi",
+    "github.com/mastahyeti/certstore",
+    "github.com/mastahyeti/cms",
+    "github.com/mastahyeti/cms/protocol",
+    "github.com/mastahyeti/fakeca",
+    "github.com/pborman/getopt/v2",
+    "github.com/pkg/errors",
+    "github.com/stretchr/testify/require",
+    "golang.org/x/crypto/openpgp/packet",
+    "golang.org/x/crypto/openpgp/s2k",
+  ]
   solver-name = "gps-cdcl"
   solver-version = 1
diff --git a/Gopkg.toml b/Gopkg.toml
index d86a943..e71e016 100644
--- a/Gopkg.toml
+++ b/Gopkg.toml
@@ -27,7 +27,7 @@
 
 [[constraint]]
   name = "github.com/mastahyeti/certstore"
-  version = "0.0.3"
+  version = "0.0.4"
 
 [[constraint]]
   name = "github.com/mastahyeti/cms"
diff --git a/vendor/github.com/mastahyeti/certstore/certstore_windows.go b/vendor/github.com/mastahyeti/certstore/certstore_windows.go
index 8c09e97..5320de9 100644
--- a/vendor/github.com/mastahyeti/certstore/certstore_windows.go
+++ b/vendor/github.com/mastahyeti/certstore/certstore_windows.go
@@ -134,7 +134,7 @@ func (s *winStore) Identities() ([]Identity, error) {
 		idents = append(idents, newWinIdentity(chain))
 	}
 
-	if err = lastError("failed to iterate certs in store"); err != nil && errors.Cause(err) != errCode(CRYPT_E_NOT_FOUND) {
+	if err = checkError("failed to iterate certs in store"); err != nil && errors.Cause(err) != errCode(CRYPT_E_NOT_FOUND) {
 		goto fail
 	}
 
@@ -184,7 +184,7 @@ func (s *winStore) Import(data []byte, password string) error {
 	for {
 		// iterate through certs in temporary store
 		if ctx = C.CertFindCertificateInStore(store, encoding, 0, C.CERT_FIND_ANY, nil, ctx); ctx == nil {
-			if err := lastError("failed to iterate certs in store"); err != nil && errors.Cause(err) != errCode(CRYPT_E_NOT_FOUND) {
+			if err := checkError("failed to iterate certs in store"); err != nil && errors.Cause(err) != errCode(CRYPT_E_NOT_FOUND) {
 				return err
 			}
 
@@ -612,8 +612,19 @@ func exportCertCtx(ctx C.PCCERT_CONTEXT) (*x509.Certificate, error) {
 
 type errCode uint64
 
-// lastError gets the last error from the current thread.
+// lastError gets the last error from the current thread. If there isn't one, it
+// returns a new error.
 func lastError(msg string) error {
+	if err := checkError(msg); err != nil {
+		return err
+	}
+
+	return errors.New(msg)
+}
+
+// checkError tries to get the last error from the current thread. If there
+// isn't one, it returns nil.
+func checkError(msg string) error {
 	if code := errCode(C.GetLastError()); code != 0 {
 		return errors.Wrap(code, msg)
 	}